Lock slider for zipper fasteners



May 23, 1967 J. E. BURBANK LOCK SLIDER FOR ZIPPER FASTENERS Filed Jan.6. 1966 United States Patent 3,320,645 LOK SHEER FUR ZIPPER FASTENERSJohn E. Burbank, Middlebnry, Conn, assignor to Scovill Manufacturing(Jompany, Waterbury, Conn, 21 corporation of Connecticut Filed Jan. 6,1966, Scr. No. 519,090 6 Claims. ((Il. 24--2ti5.14)

This invention relates to zipper fasteners, and more particularly to animproved automatic lock slider.

Many automatic lock sliders have been devised and used involving somespring action on a locking member which is under the control of the pulltab. It has usually been considered desirable to employ a minimum numberof pieces; namely: the slider body, the pull tab and the locking member.

In adapting a single member for the normal locking functions, and alsofor secure attachment to the slider, various more or less difiicult andcomplicated shapes have been proposed. In particular, this inventionaims at an improvement in the three-piece slider of the Firing Patent2,453,660. There, the locking member is formed as one piece With thecover cap by which attachment to the slider body is made. This combinedlocking member and cap is, in common with all other known automaticlocking members, somewhat complicated and especially difiicult to feedin orderly arrangement into an automatic assembly machine. These piecesare light in weight and of unsymmetrical shape but for mechanicalassembly, they must in some manner be put in orderly arrangement. Sincethe pieces are unsymmetrical about any plane, this presents a difficultproblem and one which usually requires the constant attention of anoperator.

In the present invention, I employ separate pieces for the lock and capbut they are so simple in shape that they can be made more economicallythan one complicated piece and more importantly, they are symmetricalabout normal median planes extending transversely and longitudinally ofthe pieces. Thus, they can easily by hoppered and fed in orderlyarrangement in automatic assembly operations because they need to beoriented only in one direction.

Another advantage of my improved construction is the ability to make thelocking member itself heavier and stronger because the spring can beincorporated in the attaching cap.

Other objects and advantages of the invention will hereinafter morefully appear.

In the accompanying drawing, I have shown for purpose of illustration,two embodiments which the invention may assume in practice. In thedrawing:

FIG. 1 is a perspective view of my improved slider;

FIG. 2 is a longitudinal central section;

FIG. 3 is a perspective of the locking member;

FIG. 4 is a perspective of the cap;

FIG. 5 is a detailed section on line 55 of FIG. 2;

FIG. 6 is an enlargement of a portion of FIG. 2 to indicate thedifferent positions of the locking member and one of the springysections of the cap; and

FIG. 7 is a longitudinal section illustrating a modification.

The slider body, which is preferably die cast or molded, has the frontwing 8, the back wing 9 and the usual connection neck 10. One or both ofthe wings is provided with side flanges or rails 11 and thus, the wings,neck and flanges define a Y-shaped channel for the zipper fastenerelements. The neck end of the slider will be referred to as the upperend and of course, the narrow end of the slider, the lower end.

At the upper end of the slider body a pair of forwardly projectinglaterally spaced lugs 12 and 13 are formed ice so as to provideshoulders 14, as seen in FIG. 5. The lower end of the slider also has apair of spaced lugs 15 and 16 which are likewise provided with shoulderssimilar to the shoulders 14; and in this case, the lugs may beintegrally connected near the bottom end of the slider by the section ofmetal indicated at 17 in FIG. 2.

The locking member which is bent into shape from a simple strip of fiatmetal, fits loosely between the lugs 12 and 13 at the upper end andextends over the front wing and through a hole 18 near the lower end ofthe slider. This locking member has like-shaped inturned or right angledupper and lower end portions 19 and 20, respectively. The lower end 2'!)extends through the hole 18 into the slider channel to engage fastenerelements While the upper end is nested in a recess 21 in the slider neck10 and acts as a fulcrum for the locking member. The whole centralregion of the locking member may be referred to as an arched portion butpreferably, midway between the ends there is formed a V-shapeddepression 22 which provides inclined surfaces 23 and 24 on the backside of the locking member. Actually then, this forms two arches 25 and26 which are joined to the right angled end portions 19 and 20 byinclined sections 27 and 28, respectively. At the juncture of theseinclined sections with the right angled end portions 19 and 20, thereare shoulders 29 and 30.

Since the locking member is symmetrical as already indicated, it isimmaterial which end is uppermost in the final assembly. Duringassembly, there is first put in place the pull tab 31 with its pintleportion 32 in the space between the upper and lower sets of lugs on theslider. This pintle portion will co-operate with one or the other of theinclined sections 27 and 28 to lift the locking member on a downwardpull and with either of the inclined surfaces 23 and 24 on the upwardpull. To assist this outward camming action of the locking member, theremay also be provided upper and lower ramps 33 and 34 on the slider body.

The parts are held together by the cap shown in FIG. 4. This is alsosimply sheared from a piece of strip metal and bent to shape and islikewise symmetrical about both the normal median transverse andlongitudinal planes. The cap has a central wide section 35 which fillsin the space between the upper and lower lugs 12 and 13 in the sliderbody, and like-shaped curved springy end sections 36 and 37 which arejoined to the central portion 35 by the anchor sections 38 and 39fitting against the shoulders 14 of the lugs 12, 13, 15 and 16. The capcan be dropped into place without regard to its endwise orientation andsecured by bending over the edge portions 40 of all of the lugs in themanner indicated in FIG. 5.

One or the other of the springy ends 36 and 37 will bear against thelocking member near to, but at some distance from the fulcrum end, andpreferably, this hearing is against one of the shoulders 29 or 30. Thespringy end portion which happens to come at the lower end of the sliderhas no function except to make a neat cover for the lower end of thefront wing. The movement of the locking member and the active springysection of the cap is best depicted in FIG. 6 where the full lines showthe locked position and the dotted lines, the unlocked position. In themodification shown in FIG. 7, all parts are the same in general, exceptfor the cap and except for the absence of shoulders 29 and 30 on thelocking memher.

The cap is made somewhat longer and springy extensions 41 and 42 arebent upon themselves so that one or the other, depending upon the waythe cap is assembled, will bear on one of the inclined portions 27 or 28depending on which way the locking member is assembled. In FIG. 7, thereis also shown another possibility. The lower lugs and 16 do not projectas far forwardly as the upper lugs 12 and 13. The cap can, nevertheless,be made symmetrical initially and forced into place during assembly.This construction has the advantage that outside pressure as from aflatiron will be borne largely in the upper region of the slider which,of course, is best adapted to resist such pressure.

In operation, one of the springy extensions of the cap bearing againstthe locking member will normally urge the lower end portion 19 or 29 asthe case may be, into locking position as seen in full lines in FIG. 2.One of the shouldered portions 29 and 36 of the locking member will bearagainst a shoulder 44 formed in the front wing to limit the inwardmovement of the locking member. When a force to applied to the pull tab31, either upwardly, downwardly or straight forwardly, the lockingmember will, of course, be lifted so that the parts assume the dottedline position seen in FIG. 2, and the cap itself will limit outwardmovement of the locking member and transmit any further pulling force tothe slider.

The important advantages of making the parts symmetrical so that theycan be easily hoppered and assembled will more than ofiset thedisadvantage of having an extra piece, especially since the partsthemselves are so simple and so easily made. Furthermore, the lockingmember can be made of any desired thickness of material for strengthbecause the spring action is derived from the cap. 7

What I claim is:

1. A slider for zipper fasteners comprising (a) a rigid body memberhaving front and back wings joined by a neck at one end and providing aY-, shaped channel, that end of the slider having the neck being hereincalled the upper end;

(b) a pair of laterally spaced lugs projecting forwardly from the upperend portion of the slider;

(c) a locking member fitting loosely between said lugs and extendinglengthwise over said front Wing, said locking member having like-shapedinturned end portions, the upper one of which rests in a recess in saidslider neck to provide a fulcrum for the locking member, while the lowerinturned end portion extends through a hole in said front wing near thelower end of the slider and moves in and out of said channel as thelocking member is tilted inwardly or outwardly about said fulcrum, saidlocking member being symmetrical about a plane extending at right anglesthrough the locking member midway between its ends and also about aplane extending at right angles to said first plane and through thelongitudinal center line of said locking member, said locking memberhaving an arched portion intermediate said ends;

(d) a pull member having a pintle portion extending through said archedportion; and

(e) a cap extending over said locking member, said cap being anchored tosaid lugs and also to the lower end portion of said front wing, said caphaving springy tongues at opposite ends, the upper one of which bearsagainst said locking member at a point spaced from said fulcrum to urgesaid locking member to locking position, said pull member serving totilt said locking member forwardly to unlocked position. 7

2.. A slider as defined in claim 11, wherein said locking member is arigid strip of fiat metal bent to shape.

3. A slider as defined in claim 1, wherein said locking member has acentrally located V-shaped depression providing an inclined surface onthe back side to co-operate with the pull tab in the movement of thelocking member, thus dividing the middle region of the locking memberinto two arched portions-which connect with said inturned end portionsby inclined sections.

4. A slider as defined in claim ll, wherein said cap is likewisesymmetrical about normal median, transverse and longitudinal planes.

5. A slider as defined in claim 1, wherein the anchoring means for thelower end of said cap comprises a second pair of laterally spaced lugs.

6. A slider as defined in claim 5, wherein said second pair of lugs donot project as far forwardly as the other pair.

References Cited by the Examiner UNITED STATES PATENTS 2,453,660 11/1948Firing 24205.14

FOREIGN PATENTS 578, 141 6/ 1946 Great Britain. 851,767 10/ 1960 GreatBritain. 853,9Q5 11/1960 Great Britain 978,831 12/1964 Great Britain.

BERNARD A. GELAK, Primary Examiner.

1. A SLIDER FOR ZIPPER FASTENERS COMPRISING (A) A RIGID BODY MEMBERHAVING FRONT AND BACK WINGS JOINED BY A NECK AT ONE END AND PROVIDING AYSHAPED CHANNEL, THAT END OF THE SLIDER HAVING THE NECK BEING HEREINCALLED THE UPPER END; (B) A PAIR OF LATERALLY SPACED LUGS PROJECTINGFORWARDLY FROM THE UPPER END PORTION OF THE SLIDER; (C) A LOCKING MEMBERFITTING LOOSELY BETWEEN SAID LUGS AND EXTENDING LENGTHWISE OVER SAIDFRONT WING, SAID LOCKING MEMBER HAVING LIKE-SHAPED INTURNED ENDPORTIONS, THE UPPER ONE OF WHICH RESTS IN A RECESS IN SAID SLIDER NECKTO PROVIDE A FULCRUM FOR THE LOCKING MEMBER, WHILE THE LOWER INTURNEDEND PORTION EXTENDS THROUGH A HOLE IN SAID FRONT WING NEAR THE LOWER ENDOF THE SLIDER AND MOVES IN AND OUT OF SAID CHANNEL AS THE LOCKING MEMBERIS TILTED INWARDLY OR OUTWARDLY ABOUT SAID FULCRUM, SAID LOCKING MEMBERBEING SYMMETRICAL ABOUT A PLANE EXTENDING AT RIGHT ANGLES THROUGH THELOCKING MEMBER MIDWAY BETWEEN ITS ENDS AND ALSO ABOUT A PLANE EXTENDINGAT RIGHT ANGLES TO SAID FIRST PLANE AND THROUGH THE LONGITUDINAL CENTERLINE OF SAID LOCKING MEMBER, SAID LOCKING MEMBER HAVING AN ARCHEDPORTION INTERMEDIATE SAID ENDS; (D) A PULL MEMBER HAVING A PINTLEPORTION EXTENDING THROUGH SAID ARCHED PORTION; AND (E) A CAP EXTENDINGOVER SAID LOCKING MEMBER, SAID CAP BEING ANCHORED TO SAID LUGS AND ALSOTO THE LOWER END PORTION OF SAID FRONT WING, SAID CAP HAVING SPRINGYTONGUES AT OPPOSITE ENDS, THE UPPER ONE OF WHICH BEARS AGAINST SAIDLOCKING MEMBER AT A POINT SPACED FROM SAID FULCRUM TO URGE SAID LOCKINGMEMBER TO LOCKING POSITION, SAID PULL MEMBER SERVING TO TILT SAIDLOCKING MEMBER FORWARDLY TO UNLOCKED POSITION.